ByHannah Allam, McClatchy NewspapersMarch 3, 2010

A campaign poster of Dr. Maha al-Dori, of the Iraqi National Alliance, is seen in Sadr City, Baghdad, Iraq, Wednesday. Three powerful suicide bombings killed at least 33 people and wounded more than 50 Wednesday morning in the run-up to Sunday’s Iraq election.

Baghdad — Three powerful suicide bombings killed at least 33 people and wounded more than 50 Wednesday in the restive Diyala province northeast of Baghdad, authorities said. Most of those killed and wounded were Iraqi police officers charged with securing the province's capital city ahead of national elections Sunday in Iraq.

The blasts occurred in quick succession, targeting police buildings in Baqouba, the capital of Diyala, where local authorities are still battling Sunni Muslim extremists. The insurgents use the area’s orchards and farmlands to hide out since U.S. and Iraqi offensives drove them from Baghdad and the west.

The attacks were the deadliest so far in the tense period ahead of Iraq’s parliamentary elections. Security forces imposed a full curfew on the city, clearing the streets even of pedestrians until further notice.

“The timing is a message to prevent people from participating in elections, because it happened just a few days before the general voting and less than 24 hours before the special vote for security forces,” said Maj. Ghalib Atiyah al Jubouri, a spokesman for Diyala's police. “We feel people will challenge this message and reject it. … I’m sure they’ll turn out for the elections in force.”

Jubouri said the first bomber drove a car packed with explosives and detonated it outside the station of a police quick-reaction force at about 9 a.m. Five minutes later, Jubouri said, a second car driven by a suicide bomber exploded outside a police personnel office.

At about 10 a.m. local time, as the Diyala police chief was visiting the wounded in Baqouba General Hospital, a third bomber wearing a suicide vest blew himself up inside the hospital, Jubouri said. He said the bomber entered the compound in an ambulance, dressed in a police lieutenant’s uniform and pretending to be wounded. The police chief was unhurt in the blast.

“Unfortunately, this happened because police uniforms are everywhere in the market,” Jubouri said. “It’s a really big mistake, and it should be addressed.”

Police said they had four suspects in custody. Top officials of Diyala’s police, the Iraqi army and intelligence services met for hours after the bombings, Jubouri said.

(McClatchy special correspondents Laith Hammoudi in Baghdad and an Iraqi reporter in Baqouba, who can't be named for security reasons, contributed to this article.)